How to convert psd(photoshop file) or tiff to PNG using Ghostscript?

I am attempting to use Ghostscript to convert PSD, TIFF, PCX...files to PNG file. Using ghostscript 9.04, EPS or PDF is work that convert to PNG. But failed psd(same tiff, pcx) file. Error message is 'Error: /undefined in 8BPS'(tiff is '/undefined in II').

I tried on windows7 and visualstudio 2008.

Solution

Ghostscript consumes PostScript or PDF, it does not consume image formats. You are trying to use the wrong tool, export them as PNG from your image application.